Tetrahydrofuran → 2-[(4,4-Diethoxy-2-butyn-1-yl)oxy]tetrahydropyran

HRID 1488618Notes

Reaction equation

HRID 1488618 reaction equation
C([Mg]Br)C.C1COCC1.[CH2:10]([O:13][CH:14]1[CH2:19][CH2:18][CH2:17][CH2:16][O:15]1)[C:11]#[CH:12].[CH2:20]([O:22][CH:23](OCC)[O:24][CH2:25][CH3:26])[CH3:21]>C1(C)C=CC=CC=1>[CH2:20]([O:22][CH:23]([O:24][CH2:25][CH3:26])[C:12]#[C:11][CH2:10][O:13][CH:14]1[CH2:19][CH2:18][CH2:17][CH2:16][O:15]1)[CH3:21]

Participants

6

Reactant 4

HCID 8028TetrahydrofuranHCID 31214Ethyl orthoformateHCID 98609Tetrahydro-2-(2-propynyloxy)-2H-pyranHCID 178418443HCID 178418443, compound

Product 1

HCID 136446252-[(4,4-Diethoxy-2-butyn-1-yl)oxy]tetrahydropyranYield 79%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent2×

Procedure

A 1M solution of ethylmagnesium bromide in THF (200 ml, 0.2 mol) was treated with 29 ml (0.2 mol) of a solution of 3,4,5,6-tetrahydro-2-(2-propynyloxy)-2H-pyran in toluene, while maintaining ambient temperature through use of a cool water bath. The resulting solution was stirred for 4 h and treated with 47 ml (0.28 mol) of a solution of triethylorthoformate in toluene, while maintaining ambient temperature with a cool water bath. The resulting solution was heated to 85° C. for 8 h, allowing the removal of THF by distillation. After being allowed to cool, the resulting solution was poured into 500 ml of ice-water containing 29 g of NH4OAc, extracted with two portions of ether, added over K2CO3, and concentrated in vacuo. The residue was distilled at ca. 0.5 mm Hg pressure (b.p. 103°-108° C.) to provide 39.5 g (79%) of the desired compound. 1H NMR (CDCl3) δ 1.24 (t, J=7 Hz, 6H), 1.5-1.9 (m, 6H), 3.5-3.65 (m, 3H), 3.7-3.9 (m, 3H), 4.32 (AA', 2H), 4.81 (m, 1H), 5.31 (m, 1H). Mass spectrum: (M+NH4)+ =260.

Workup

  1. temperaturewhile maintaining ambient temperature with a cool water bath
  2. temperatureThe resulting solution was heated to 85° C. for 8 h
  3. customthe removal of THF
  4. distillationby distillation
  5. temperatureto cool
  6. additionthe resulting solution was poured into 500 ml of ice-water containing 29 g of NH4OAc
  7. extractionextracted with two portions of ether
  8. additionadded over K2CO3
  9. concentrationconcentrated in vacuo
  10. distillationThe residue was distilled at ca. 0.5 mm Hg pressure (b.p. 103°-108° C.)

Sources & evidence

ORD record
ord-d471238a1d5e48729d0b1248f77c00ed
Source dataset
uspto-grants-1997_10
Patent number
US05674882

Reaction notes

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